〈a, b | aab=ba, aaaa=ba〉

Properties

• Infinite non-commutative monoid

Completion parameters

• Reduction order: left-to-right a/b

Complete rewriting system

1. a⁶ ⇒ a⁵
2. ba ⇒ a⁴
3. a²b ⇒ a⁴

Right Cayley graph (truncated)

Left Cayley graph (truncated)